If GnuPG is installed on a system with existing user accounts, it is
sometimes required to populate the GnuPG home directory with existing
files. Especially a 'trustlist.txt' and a keybox with some
initial certificates are often desired. This scripts help to do this
by copying all files from '/etc/skel/.gnupg' to the home
directories of the accounts given on the command line. It takes care
not to overwrite existing GnuPG home directories.